Embodiments of the invention relate to gap control. More particularly, embodiments of the invention relate to gap control for a coiler.
Hot strip mill coilers are used for coiling strips of material such as, for example, steel into rolls to facilitate transport of the strip material to other locations for further processing. As the strip material is often metal or some other heavy material, and because the resulting rolls of strip material are often very large and heavy, proper control of the strip material during the coiling process is very important.
One method of controlling the strip material during coiling is to use a plurality of wrapper rolls (also known as blocker rolls or unit rolls) to press the strip material against a mandrel to tightly wrap the strip material around the mandrel and form the desired coil of strip material. The wrapper rolls can be controlled by using closed loop force regulation. Closed loop force regulation uses pressure transducers connected to each wrapper roll or connected to other structure connected to each wrapper roll such as, for example, hydraulic cylinders.
Roll gap control apparatuses of the invention have a first roll position detector for detecting a first position of a first roll, a second roll position detector for detecting a first position of a second roll and a third roll position detector for detecting a first position of a third roll. A processor determines a second position of the first roll based on the first position of the second roll and the first position of the third roll.
In some roll gap control apparatuses of the invention, the second position of the first roll is expressed as a first gap between the first roll and a first surface, the first position of the second roll is expressed as a second gap between the second roll and a second surface, the first position of the third roll is expressed as a third gap between the third roll and a third surface, and the first gap is determined by averaging the second gap and the third gap.
Strip mill coilers of the invention have a mandrel, a first roll for positioning a strip material around the mandrel, a second roll for positioning the strip material around the mandrel, and a third roll for positioning the strip material around the mandrel. A first roll position detector detects a first position of the first roll, a second roll position detector detects a first position of the second roll, a third roll position detector detects a first position of the third roll, and a processor determines a second position of the first roll based on the first position of the second roll and the first position of the third roll.
Methods of the invention detect a first position of a first roll, detect a first position of a second roll, detect a first position of a third roll, and determine a second position of the first roll based on the first position of the second roll and the first position of the third roll.
Computer programs of the invention have instructions for detecting a first position of a first roll, detecting a first position of a second roll, detecting a first position of a third roll, and determining a second position of the first roll based on the first position of the second roll and the first position of the third roll.
These and other features of the invention will be readily apparent to those skilled in the art upon reading this disclosure in connection with the attached drawing figures.